function [f,J] = create_func()

a = 0.1;
b = 0.3;
r = 1.0;

syms x y z
f_sym = [(x-a)^2 + (y-b)^2 - r^2 ; z - x*y];

J_sym = jacobian(f_sym, [x,y,z]);

f = matlabFunction(f_sym, 'Vars', [x,y,z]);

J = matlabFunction(J_sym, 'Vars', [x,y,z]);

end